Various devices have been proposed for lifting or placing sheets of wall board or comparable panels. Representative are thin plywood sheets, particle board, wall board and similar building materials. The devices are effective to lift, position and hold the sheets against the receiving abutment while the sheets are being permanently fastened. A typical apparatus of this type is disclosed in U.S. Pat. No. 2,465,206 which discloses a vertical standard supported by a frame. A rack is slidably received in the standard and supports at its upper end a generally rectangular sheet holder or panel holder. A pinion meshes with the rack and is rotated by a crank to elevate the rack and urge the sheet holder toward the ceiling with a sheet of wall board borne on the sheet holder. In upper position the wall board is disposed against the ceiling so that the wall board can be nailed or otherwise fastened in place.
There is some disadvantage in that some of the mechanism is relatively large and bulky in order to handle panels or sheets appropriately and the device is somewhat expensive to manufacture.
U.S. Pat. No. 3,487,952 discloses a duty unit which is suitable for installing heavy sheet rock or like material on ceilings. However, the apparatus is quite complicated in construction and is costly as well as bulky. This means that small sheet rock installation firms and the like are not in a position to utilize the apparatus and the equipment rental companies likewise are precluded by high capital costs from freely utilizing the structure.